Abstract：Based on the conceptual model of high-level radioactive wastes(HLW) repository，the temperature field，stress field and deformation field of HLW repository surrounding rock are calculated under the condition of thermo-mechanical(TM) coupling by using finite difference program FLAC3D. From this study，the thermo- mechanical characteristic of granite is obtained primarily under the given canister heat source and the decay law function is presented. These results show that the reasonable spacing between disposal hole is 8–12 m，and the peak temperature of the canister surface is 130 ℃，the centerline temperature among pits is about 40 ℃，which lasts for about hundreds of years under given heating output at depth of －500 m.
